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Selekce potravy bobrem evropským (Castor fiber) v hospodářských porostech jižní Moravy
Černíková, Karla
The bachelor's thesis deals with the selection of food of European beaver (Castor fiber) in the Tvrdonicko area, specifically in the surrounding stands of six blind branches of the Morava River. Czech and foreign literary sources served as the basis for the literary part of the work. For the practical part of the work, data from the field survey, which took place in the winter period of 2017 and 2018, were used. The most preferred tree species in this area were poplar (Populus sp.), babyka maple (Acer campestre), willow (Salix sp.), ash (Fraxinus sp.) and blackthorn (Prunus spinosa). The beaver preferred the most young stands with individuals of smaller diameters. The damage to the vegetation was very low compared to other localities. The results of this work mostly confirm the information presented so far on the selection of woody plants by a beaver. It also focuses on evaluating the factors that influence food choices.
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Community structure of soil saprophagous mites and their food selection
Jourová, Barbora ; Smrž, Jaroslav (advisor) ; Hubert, Jan (referee)
Community structure of soil saprophagous mites illustrates not only their diversity, but also it is able to characterize biotop as a whole. Such structure can be correlated with fluctuation of factors in with respect to the historical development and perspectives of biotope. Therefore, community structure exhibits the dynamics. The nutritional biology belongs to biological as well as to ecological parameters. This work presents the summary of existing knowledge about study of nutritional bi- ology and community structure of soil saprophagous mites and also critical analysis of methods studying soil mites. Keywords: moss mites, community strukture, food selection.
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The diet of larval and juvenile pikeperch (.i.Stizostedion lucioperca./i.)(L.)), comparative study of fishponds and a reservoir
Peterka, Jiří ; Matěna, Josef ; Lipka, J.
Diet of larval and juvenile pikeperch (.i.S. lucioperca./i.) reared in ponds was investigated and compared with the diet of pikeperch from a reservoir. Numbers of rotifers were found low in the diet of pikeperch larvae in fishponds and they were soonreplaced by nauplii of cyclopoid copepods. .i.Daphnia./i. spp. were consumed from the onset of exogenous feeding. Another smaller cladoceran .i.Bosmina./i. longirostris did not contribute to the diet significantly. In the reservoir, rotifers were not found in the diet of pikeperch larvae. Dominant food items were nauplii and 1st copepodite instar of .i.Eudiaptomus gracilis./i. and .i.Cyclops./i. spp. .i.Daphnia galeata./i. and to a lesser extent .i.Diaphanosoma brachyurum./i. appeared in the pikeperch diet at a length of about 10 mm. A shift towards larger prey, especially .i.Leptodora kindtii./i., could be recognised in pikeperch at a length of 20 mm. Growth of pikeperch was found faster in nursing ponds than in the reservoir.
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